The format of table entries is: opcode, operands. A line may contain only
one entry. The opcode is a number and tells the grade 2 compiler how to
handle the entry. The number 0 can be used to define mnemonic synonyms for
these numbers, such as "opcode" for 0 itself. In an entry, the opcode and
the operands are separated by blanks or tabs. more than one blank or tab is
ignored. Leading blanks at the beginning of lines are also ignored. Blank
lines and lines beginning with '#' are ignored. Lines containing table
entries may also contain comments following the entry and separated from the
last operand by at least one blank or tab. Most entries have two operands,
but the number is determined by the opcode.

Define the opcodes.
Opcodes must be defined before they are used. Except for this restriction,
the order of the entries in the table may be anything that is convenient.
You may wish to bear in mind, however, that the compiler arranges entries so
that the longest of several entries beginning with the same two characters
is tested first. If entries have the same first operand, they are arranged
in the order in which they are found in the table. Thus, the same string may
have different translations under different circumstances. This method of
arrangement is also followed for entries whose first operand is just one
character.
In specifying the first operand, you may simply type it, if all the
characters are on the keyboard. For those characters which are not, use a
backslash followed by two hexadecimal digits. If you wish, you can follow
the C convention and place "0x" between the backslash and the hexadecimal
digits. To enter a backslash, use two in sequence, "\\".

In most entries, the first operand is the string to be translated, and the
second operand is the dot patterns of the Braille cells in the translation.
The standard dot numbering is used. Cells are separated by hyphens ('-').
